CN102726045A - Spatial prediction technique for video coding - Google Patents

Abstract

The invention relates to a method for coding a block of pixels comprising the following steps: determining (10), for each pixel of the current block, a prediction pixel by thresholding, with a current threshold value, of coefficients resulting from a transformation applied on a window covering at least the pixel of the current block and by inverse transformation applied to the thresholded coefficients, - extracting (12) from the current block a prediction block formed of prediction pixels to generate a residue block, and - coding (14) said residue block. According to the invention, the current threshold value is determined or coded from neighbouring reconstructed pixels of the current block.

Description

The spatial prediction technology of video coding

Technical field

The present invention relates to the general field of image encoding.

The present invention relates more specifically to the method for coded picture block and the method for decoded image blocks.

Background technology

Well-known in the prior art, an image of coded video sequences is that this image division is become block of pixels, then through spatial prediction (INTRA pattern) or time prediction (INTER pattern) each piece of encoding.The coding current block generally comprise through, for example, the DCT (discrete cosine transform) of the difference (difference) between the pixel of current block and the pixel of predict blocks is transformed into coefficient block.This coding further comprises quantization parameter, then the coefficient of entropy coding quantification.

Well-known in the prior art, with the INTRA pattern, that is, and through the spatial predictive encoding current block be from before predict current block the view data of spatial neighbor (neighbouring) piece of coding.For example, well-known in video encoding standard H.264, above being in current block or the pixel on the current block left side, predict current block.More particularly, the pixel of current block is predicted according to preferred prediction direction (for example, level, vertical etc.) and the contiguous pixel of current block through linear combination.Predict pixel, that is, the predict pixel of the neighborhood pixels gained of linear combination current block forms predict blocks.When current block to be predicted comprised profile, this Forecasting Methodology was especially effective.In fact, if the edge of an object corresponding to by one of prediction direction of standard definition H.264 the time, this profile is in fact expanded in current block to be predicted with one way system.But when having two-dimensional structure, this Forecasting Methodology has been lost its efficient.

Summary of the invention

The objective of the invention is to overcome at least one shortcoming of prior art.For this reason, the present invention relates to be called the method for the block of pixels of current block through spatial predictive encoding.Comprise following steps according to coding method of the present invention:

-through utilizing current threshold value that the coefficient of the conversion gained on the window that is applied in the pixel that covers current block is at least added threshold and through being applied to add the inverse transformation of threshold coefficient, for each pixel of current block is confirmed predict pixel;

-from current block, extract the predict blocks that forms by predict pixel with the generation residual block; And

-coded residual piece.

Advantageously, definite or this current threshold value of coding from the contiguous reconstructed pixel of current block.In definite from the contiguous reconstructed pixel of current block or this current threshold value of coding, improved code efficiency.

According to a specific embodiment, utilize each threshold values of a plurality of threshold values to repeat to confirm the step of predict pixel for each pixel of current block.This method also comprises and is chosen in the minimum threshold value of the predicated error calculated between current block and the predict blocks in the middle of a plurality of threshold values as current threshold value.

According to a particular aspects of the present invention, through with the prediction threshold value the current threshold value of differential coding, this predicted value depends on the contiguous reconstructed pixel of current block.

According to particular characteristics, this prediction threshold value equals to be used in the mean value of the threshold value in the contiguous block of current block.

According to first modification, this prediction threshold value equals to be used in the intermediate value of the threshold value in the contiguous block of current block.

According to second modification, this prediction threshold value is confirmed according to following steps:

-through utilizing threshold value that the coefficient that is applied in the conversion gained on the window that covers reconstructed pixel is at least added threshold and through being applied to add the inverse transformation of threshold coefficient, for each reconstructed pixel in the adjacent domain of current block is confirmed predict pixel;

-utilize each threshold values of a plurality of threshold values to repeat to confirm the step of predict pixel for each pixel of adjacent domain; And

-be chosen in the minimum threshold value of the predicated error calculated between reconstructed pixel and the respective predicted pixel of adjacent domain of current block in the middle of a plurality of threshold values as the prediction threshold value.

According to another embodiment, this current threshold value is confirmed according to following steps:

-through utilizing threshold value that the coefficient that is applied in the conversion gained on the window that covers reconstructed pixel is at least added threshold and through being applied to add the inverse transformation of threshold coefficient, for each reconstructed pixel in the adjacent domain of current block is confirmed predict pixel;

-utilize each threshold values of a plurality of threshold values to repeat to confirm the step of predict pixel for each pixel of adjacent domain; And

-be chosen in the minimum threshold value of the predicated error calculated between reconstructed pixel and the respective predicted pixel of adjacent domain of current block in the middle of a plurality of threshold values as current threshold value.

Advantageously, for each reconstructed pixel of the adjacent domain of current block, the predicated error of between the reconstructed pixel of the adjacent domain of current block and respective predicted pixel, calculating is considered their distances with respect to the edge of current block.

According to another aspect of the present invention, when having selected current threshold value for the current block of size 8 * 8, multiply by through the current threshold value that will select strict with 1 alpha, for each piece of the size 4 * 4 of current block calculates current threshold value.

Advantageously, the size of window depends on pixel to be predicted position in current block.

The invention still further relates to the method through the current block of spatial prediction decoded pixel, it comprises following steps:

-decoded residual piece;

-through utilizing current threshold value that the coefficient of the conversion gained on the window that is applied in the pixel that covers current block is at least added threshold and through being applied to add the inverse transformation of threshold coefficient, for each pixel of current block is confirmed predict pixel; And

-through residual block that merges decoding and the said current block of predict blocks reconstruct that forms by predict pixel.

Advantageously, from the contiguous reconstructed pixel of current block, confirm this current threshold value.

According to a specific embodiment, this current threshold value is confirmed according to following steps:

-through utilizing threshold value that the coefficient that is applied in the conversion gained on the window that covers reconstructed pixel is at least added threshold and through being applied to add the inverse transformation of threshold coefficient, for each reconstructed pixel in the adjacent domain of current block is confirmed predict pixel;

-utilize each threshold values of a plurality of threshold values to repeat to confirm the step of predict pixel for each pixel of adjacent domain; And

-be chosen in the minimum threshold value of the predicated error calculated between reconstructed pixel and the respective predicted pixel of adjacent domain of current block in the middle of a plurality of threshold values as current threshold value.

According to another specific embodiment, also comprise following steps according to coding/decoding method of the present invention:

The difference of-decoding threshold value;

-definite prediction threshold value from the contiguous reconstructed pixel of current block; And

This difference of-calculating and this prediction threshold value sum are somebody's turn to do and value is current threshold value.

Advantageously, this prediction threshold value is confirmed according to following steps:

-through utilizing threshold value that the coefficient that is applied in the conversion gained on the window that covers reconstructed pixel is at least added threshold and through being applied to add the inverse transformation of threshold coefficient, for each reconstructed pixel in the adjacent domain of current block is confirmed predict pixel;

-utilize each threshold values of a plurality of threshold values to repeat to confirm the step of predict pixel for each pixel of adjacent domain; And

-be chosen in the minimum threshold value of the predicated error calculated between reconstructed pixel and the respective predicted pixel of adjacent domain of current block in the middle of a plurality of threshold values as the prediction threshold value.

Description of drawings

Through with reference to accompanying drawing by restrictive embodiment and favourable implementation anything but, can understand better and illustration the present invention, in the accompanying drawings:

-Fig. 1 shows according to coding method of the present invention;

-Fig. 2 shows and comprises to be predicted image section with the window that is used to predict this piece;

-Fig. 3 and 4 shows in detail the step according to coding method of the present invention;

-Fig. 5 and 6 shows and comprises to be predicted image section with the different windows that is used to predict this piece;

-Fig. 7 show comprise to be predicted, with the contiguous cause and effect band Zc of this piece be used to predict the image section of window of the pixel of this cause and effect band;

-Fig. 8 illustrates according to coding/decoding method of the present invention;

-Fig. 9 illustration according to encoding device of the present invention; And

-Figure 10 shows according to decoding device of the present invention.

Embodiment

Image comprises each pixel or picture point of being associated with at least one item of image data.One item of image data is, for example, and a brightness data or a chroma data.

The data that obtain after other data have been extracted in term " residual error " expression.This extraction generally is from source pixel, to deduct predict pixel.But this extraction is more general, especially comprises weighted subtraction.

Term " reconstruct " expression merges the data (for example, pixel, piece) that obtain afterwards with residual error and prediction data.This merging generally is a residual prediction pixel sum.But this merging is more general, and especially comprises weighting summation.Reconstructed blocks is the piece of reconstructed pixel.

About picture decoding, term " reconstruct " and " decoding " are often as synonym.Therefore, " reconstructed blocks " is also illustrated under the term of " decoding block ".

The present invention relates to be called the method for the block of pixels of current block through spatial predictive encoding.It is applied to the coding of image or image sequence.According to coding method of the present invention based on the method that is described in the extrapolated signal in the following document: Guleryuz; O.G.; Title is " Nonlinear approximation based image recovery using adaptive sparse reconstructions and iterated denoising ", Image Processing, IEEE Transactions volume 15; 3 phases, in March, 2006 page or leaf: 539-571.This Extrapolation method is used to shelter the purpose of (masking) mistake at first.

The method of describing according to the current block of coded image of the present invention with reference to figure 1 below.

During step 10, for each pixel of current block is confirmed predict pixel.Predict pixel forms the predict blocks of current block.Predict pixel is through utilizing current threshold value that the coefficient of the conversion gained on the window that is applied in the pixel that covers current block to be predicted is at least added threshold (thresholding) acquisition.This window is corresponding to the support of conversion.The conversion of using is, for example, and DCT.But the present invention is not limited to the latter.Also can use other conversion as the DFT.According to the present invention, from the contiguous reconstructed pixel of current block, confirm or the current threshold value of encoding.When from the contiguous reconstructed pixel of current block, confirming or encoding current threshold value, improved code efficiency.

During step 12, from current block, extract the predict blocks that forms by predict pixel with the generation residual block.

During step 14, residual block is coded among the stream S.For example, through, for example, DCT or wavelet transformation are transformed into coefficient block with residual block, and it is quantized then and is encoded through entropy coding.According to a kind of modification, only quantize then through entropy coding coded residual piece.

With reference to figure 2 and 3 step 10 of confirming predict pixel is described more accurately below.In Fig. 2, predict pixel p _0,0Corresponding to the pixel on the upper left side of current block B to be predicted.Pixel with the cross sign in Fig. 2 is a known pixels, that is, and and reconstructed pixel.Predict pixel p _0,0Give it so that will represent the value of its environment.Window F is at its initial position F _0,0On cover pixel p to be predicted at least _0,0In step 10, on this window, use conversion exactly.

During step 100, to pixel p _0,0Specify initial value.As a simple case, will specify to pixel p from the mean value of neighborhood pixels _0,0This value representation is become p _Av0,0: p _Av0,0=(a+b+c)/3.According to a kind of modification, the intermediate value of pixel a, b and c is specified to pixel p _0,0According to another modification, will be worth one of a, b or c and specify to pixel p _0,0According to other modification, consider to be in pixel p _0,0The cause and effect adjacent domain in other pixel, think pixel p _0,0Confirm initial value.The cause and effect adjacent domain of current pixel is included in the pixel groups of the present image of reconstruct during coding (correspondingly decoding) current pixel.

During step 110, conversion is applied to the pixel of window F.Then these pixels are transformed into coefficient.

During step 120, use threshold value th _OptIn transform domain, coefficient is added threshold.This threshold that adds has the noise of elimination so that only remain with the effect of meaning coefficient.

During step 130; The inverse transformation that is applied in the conversion of using in the step 110 is to turn back to pixel domain; So that recovery table is shown as the new predicted pixel values of , the index greater than of null value is corresponding to the zero offset with respect to the initial position of this window of the row and column of window F.

With reference to Figure 4 and 5, utilize window F offset applications with reference to the identical method of figure 3 described methods, think that other pixel of current block B is confirmed predict pixel.(iteratively) predict pixel p repeatedly _0,0To p _{N-1, m-1}Position F with respect to the window F among Fig. 3 _0,0, with window 1 pixel that squints to the right, so as to confirm with current block just in time in pixel p _0,0The corresponding predict pixel p of pixel on the right _0,1In Fig. 5, a, b and c are in pixel p to be predicted respectively _0,1The left side, the pixel p on the top and diagonal angle _0,1Contiguous reconstructed pixel, wherein, more particularly, under present case, the pixel of inserting in before a equals Value.

According to a kind of modification, with position F _0,0On window 2 pixels that squint to the right, that is, be displaced to position F _0,2In this situation, in second repeats, predict pixel p _0,1And p _0,2More generally, can be with m pixel with m pixel of window F skew.For prediction is too demoted, it is favourable that the value of m keeps less.

During step 100, will specify to p from the mean value of neighborhood pixels _0,1, for example, this value is

This value representation is become Also can be applied in reference pixel p in the step 100 _0,0Described modification.

During step 110, conversion is applied to window F _0,1Pixel.Then these pixels are transformed into coefficient.

During step 120, utilize threshold value th _OptIn transform domain, coefficient is added threshold.This threshold that adds has the noise of elimination so that only remain with the effect of meaning coefficient.

During step 130; The inverse transformation that is applied in the conversion of using in the step 110 turns back to pixel domain; So that recovery table is shown as the new predicted pixel values of

, the index greater than

is listed as with 1 corresponding to window F 0 row that squinted.As shown in Figure 5, pixel p _0,0Be included in position F _0,1On window F in.Therefore, calculating predict pixel p _0,1During this time, also be pixel p _0,0Calculate new value.In fact, during inverse transformation, will be worth

Specify and give pixel p _0,0This value

Can be different from when window F does not squint (window is at F in preceding repetition _0,0On the position) middle that calculates

In order to be thought of as pixel p _0,0Two values calculating, that is, window F zero offset in preceding repetition, obtain that

With obtain in the current repetition that is listed as at skew 0 row and 1

To newly be worth to specify and give predict pixel p _0,0This new value that is expressed as equals; For example; The mean value of two values

and

; That is,

Repeat this method and all obtain prediction up to all pixels of piece B.For this reason, during step 140, whether the checking current pixel is to be predicted last pixel.If this situation, then the step of predict blocks is confirmed in termination.Under opposite situation, if in current line, still there is pixel to be predicted, then with the window F row that squint to the right, or with the window F delegation that squints downwards, so that once more window is placed the beginning of being expert at.But, do not fix in each mode that repeats hour offset window F.It depends on the scanning sequence for to be predicted definition.With reference to preceding figure, the scanning of pixel from left to right individual element is carried out then line by line.This scanning is not exclusive, sawtooth pattern scanning and picture, for example, the 1st row the 1st row then earlier, then the 2nd row then other such type of scanning of the 2nd row or the like also be possible.

To the reposition of window applying step 100 to 140 once more.Be new pixel p to be predicted _{Sk, sl}Determined value

The pixel that also is included among the window F for the current block that has calculated predicted value or a plurality of predicted values during the former repetition is calculated new predicted value.For these pixels, like top reference pixel p _0,0Describe, confirm new predicted value as follows:

$p_{\mathrm{Int}.k,l}^{\mathrm{sk},\mathrm{sl}}=\underset{p=k}{\overset{\mathrm{sk}}{\mathrm{\Σ}}}\underset{q=l}{\overset{\mathrm{sl}}{\mathrm{\Σ}}}\left(p_{\mathrm{tr}.k,l}^{p,q}\right)/\left((\mathrm{sk}-k+1)(\mathrm{sl}-l+1)\right),$

Wherein,

-

Be with the position F of window F _{Sk, sl}During the corresponding repetition to be predicted k the pixel of prediction in the capable and l row;

-sk and sl: the skew that is the row and column of window F respectively;

-

Be through window F is displaced to position F in succession _{Sk, sl}The position of recurrence prediction (k, the value of the predict pixel in l).

According to a kind of modification, replace weighted sum with median or histogram peak type function.

According to first embodiment, from cause and effect band Zc, that is, comprise the reconstructed pixel in the adjacent domain of current block B, but may not be adjacent with this piece, confirm threshold value th _OptThis embodiment describes with reference to figure 7.In this Fig. 7, cross is represented reconstructed pixel.Cross on the gray background representes to belong to the pixel of cause and effect band Zc.This band Zc is used to current block to be predicted and confirms threshold value.For this reason, will be applied to the pixel of this band Zc, so that be that their central each are confirmed predict pixel and are directed against several threshold value th with reference to the described method of Figure 4 and 5 _iConfirm this predict pixel.Therefore, to each threshold value th _i, calculating energy level (energy level) on band Zc.As a kind of simple illustration, this energy will calculate according to following formula:

${\mathrm{SSE}}_i=\underset{p\∈\mathrm{ZC}}{\mathrm{\Σ}}{(Y\left(p\right)-p_{\mathrm{Int}.}\left(p\right))}^2,$

Wherein,

-p representative is included in the locations of pixels in the piece;

-Y is the value of an item of image data (for example, brightness and/or colourity) of the pixel in the current block to be predicted;

-p _IntBe to threshold value th _iThe predicted value of confirming.

For band Zc, with threshold value th _ZcConfirm as and generate minimum prediction energy SSE _iThat.

According to a kind of modification, press following calculating energy:

${\mathrm{SAD}}_i=\underset{p\∈\mathrm{Bloc}\_\mathrm{NxM}}{\mathrm{\Σ}}|Y\left(p\right)-p_{\mathrm{Int}.}\left(p\right)|$

According to another modification, press following calculating energy:

$E_i=\underset{p\∈\mathrm{Bloc}\_\mathrm{NxM}}{\mathrm{Max}}|Y\left(p\right)-p_{\mathrm{Int}.}\left(p\right)|$

According to another modification, introducing the prediction errors make Zc can be according to the weighting function apart from relativization in the forward position of pixel with respect to be predicted of Zc.The value of this weighting function so basis, for example, the distance at the center of pixel with respect to be predicted and becoming makes:

$w_{8x8}(i,j)=c\×{\mathrm{\ρ}}^{\sqrt{{(i-11.5)}^2+{(j-11.5)}^2}},$

$w_{4x4}(i,j)=c\×{\mathrm{\ρ}}^{2\×\sqrt{{(i-5.5)}^2+{(j-5.5)}^2}},$

Wherein:

-c is a normalisation coefft;

-ρ=0.8；

-i and j be corresponding to the coordinate of weight coefficient in the framework of weighting windows, wherein to be predicted center for the piece of 4 * 4 and 8 * 8 yardsticks (dimension) respectively in (5.5,5.5) and (11.5,11.5);

-initial point (0,0) is on the upper left side.

The threshold value th of current block to be predicted _OptEqual th _ZcBand Zc can have especially multi-form according to the availability of neighborhood pixels.Equally, the thickness of band can surpass 1 pixel.

According to second embodiment, through utilizing different threshold value th _iThe described method of repeated reference Figure 4 and 5 and be that current block is confirmed threshold value th through the minimum threshold value of the predicated error confirming between predict blocks and current block, to calculate _Opt

Therefore, for each threshold value th _i, the calculating energy level.As a simple case, this energy will calculate according to following formula:

${\mathrm{SSE}}_i=\underset{p\∈\mathrm{Bloc}\_\mathrm{NxM}}{\mathrm{\Σ}}{(Y\left(p\right)-p_{\mathrm{Int}.}\left(p\right))}^2,$

Wherein,

-p representative is included in the locations of pixels in the piece;

-Y is the value of an item of image data (for example, brightness and/or colourity) of the pixel in the current block to be predicted;

-p _IntBe to threshold value th _iThe predicted value of confirming.

Threshold value th _OptBe to generate minimum prediction energy SSE _iThat.

According to modification, press following calculating energy:

${\mathrm{SAD}}_i=\underset{p\∈\mathrm{Bloc}\_\mathrm{NxM}}{\mathrm{\Σ}}|Y\left(p\right)-p_{\mathrm{Int}.}\left(p\right)|.$

According to another modification, press following calculating energy:

$E_i=\underset{p\∈\mathrm{Bloc}\_\mathrm{NxM}}{\mathrm{Max}}|Y\left(p\right)-p_{\mathrm{Int}.}\left(p\right)|$

The current threshold value th that confirms according to this second embodiment _OptValue by direct coding in stream S or advantageously through with prediction threshold value th _PredDifference be coded in stream S in case reduce its coding cost.

For example, prediction threshold value th _PredEqual to be the definite threshold value th of piece contiguous with current block and that encoded _OptMean value.Consider the piece on the left side, top piece and upper left.According to modification, also consider top-right.

According to another modification, prediction threshold value th _PredEqual to be the definite threshold value th of piece contiguous with current block and that encoded _OptIntermediate value.

According to another modification, prediction threshold value th _PredEqual th _ZcShould be noted that, if confirm th according to first embodiment _Opt, th then _Opt=th _Zc, in this case, the threshold value of not encoding is because can confirm it with the mode identical with coder side at decoder-side from the pixel of Zc.

According to a specific embodiment; The current block of size 8 * 8 can be predicted through following steps: be 8 * 8 and confirm current threshold value; And utilize the current threshold application that is expressed as th8 * 8 with reference to the described method of Figure 4 and 5; Perhaps be divided into four 4 * 4 with these 8 * 8; And utilize and to be expressed as will being applied in independently on each 4 * 4 with reference to the described method of Figure 4 and 5 all identical current threshold value of each piece of th4 * 4, th4 * 4th, derive from th8 * 8 according to following equation: th4 * 4=α * th8 * 8, wherein the α strictness is less than 1.

The invention still further relates to 8 described coding/decoding methods with reference to figure.

During step 20, be current block decoded residual piece.For example, the part with stream S is decoded into coefficient.Coefficient is gone to quantize, then, if be necessary, in addition conversion of the inverse transformation of the conversion through being used in coder side.Therefore obtain residual block.

During step 22, for each pixel of current block is confirmed predict pixel.Predict pixel forms the predict blocks of current block.Predict pixel is to obtain through utilizing current threshold value that the coefficient from the conversion on the window that is applied in the pixel that covers current block to be predicted is at least added threshold.This window is corresponding to the support of conversion.The conversion of using is, for example, and DCT.But the present invention is not limited to the latter.Also can use other conversion as the DFT.

During step 24, merge the reconstruct current block through residual block with predict blocks and decoding.

The step 22 of confirming predict pixel is identical with the step 10 of coding method.But, at decoder-side, threshold value th _OptUnder situation about being coded in coder side among the stream S, from this same stream, decode, or directly confirm in the reconstructed pixel from the adjacent domain of current block.

According to first embodiment, th _OptBe directly or at coded prediction value th _PredThe situation of difference (differential) under through decode value being added in this value from this stream decoding.For example, prediction threshold value th _PredEqual to be the definite threshold value th of piece contiguous with current block and that encoded _OptMean value.For example, consider the piece on the left side, top piece and upper left.According to modification, also consider top-right.

According to another modification, prediction threshold value th _PredEqual to be the definite threshold value th of piece contiguous with current block and that encoded _OptIntermediate value.

According to another modification, prediction threshold value th _PredEqual th _Zc, th wherein _ZcSuch as coder side with reference to figure 7 description confirm.

According to second embodiment, threshold value th _OptBe with from the reconstructed pixel of band the Zc, confirm with reference to the figure 7 identical mode of being described in coder side.In this case, th _OptEqual th _Zc

According to a specific embodiment that can be applied to the Code And Decode method, the size of the window F position of pixel to be predicted in current block of depending on as shown in Figure 6.In this drawing, the F in the position _0,0On window have less than F in the position _{N-1, m-1}On the size of window.This has the advantage of the correlation that improves predict blocks.For example, when current block has 4 * 4 sizes, for being in above the current block and left side edge, that is, the 1st row and the 1st pixel that lists, the size of window is 4 * 4, and for other pixel of current block, window has 8 * 8 size.The window that uses or the yardstick of a plurality of windows are not limited to 2 power (powers of 2).In fact, the present invention be not limited to be called " fast " conversion be applied to 2 ^NThe use of conversion of manyfold sample.In addition, the conversion of use may not be dispersed.

The invention still further relates to encoding device of describing with reference to figure 9 12 and the decoding device of describing with reference to Figure 10 13.In Fig. 9 and 10, but shown module is to may or may not correspond to the functional unit of discrimination unit physically.For example, some of these modules or they can be grouped in the single component together, or constitute the function of same software.On the contrary, some modules can be made up of the discrete physical entity.

With reference to figure 9, encoding device 12 receives one or more images on input.Encoding device 12 can be realized with reference to figure 1 described according to coding method of the present invention.Each image is divided into the piece of each pixel that is associated with at least one item of image data.Encoding device 12 especially realizes utilizing the coding of spatial prediction.In Fig. 9, only show encoding device 12 and coding that passes through spatial prediction or the relevant module of INTRA coding.Unshowned other module of knowing with the technical staff video encoder field realizes scramble time prediction (for example, estimation, motion compensation).Encoding device 12 especially comprised can, for example, subtract each other through individual element, from current block B, extract predict blocks Pr to generate the computing module 1200 of residual block Bres.Computing module 1200 can be realized the step 12 according to coding method of the present invention.It further comprises the module 1202 that can conversion residual block Bres then it be quantized into quantized data.Conversion T is, for example, and discrete cosine transform (or DCT).Encoding device 12 further comprises the entropy coding module 1204 that can quantized data be encoded into encoded data stream S.It also comprises the module 1206 of the inverse operation that carries out module 1202.Module 1206 is carried out re-quantization Q ^-1Carry out inverse transformation T afterwards ^-1Module 1206 is connected with computing module 1208, computing module 1208 can, for example,, merge data block and predict blocks Pr from module 1206 through the individual element addition, be stored in the reconstructed blocks in the memory 1210 with generation.

Prediction module 1216 is confirmed predict blocks Pr.Prediction module 1216 can realize the step 10 according to coding method of the present invention.The step 14 of this coding method realizes in module 1202 and 1204.

With reference to Figure 10, decoder module 13 receives the encoded data stream S of representative image on input.Stream S is that for example, encoding device 12 sends via channel.Decoding device 13 can be realized with reference to figure 8 described according to coding/decoding method of the present invention.Decoding device 13 comprise can the generating solution code data entropy decoder module 1300.Then decoded data is sent to and to carry out the module 1302 that re-quantization carries out inverse transformation then.Module 1302 is identical with the module 1206 of the encoding device 12 that generates stream S.Module 1302 is connected with computing module 1304, computing module 1304 can, for example,, merge piece and predict blocks Pr from module 1302 through the individual element addition, be stored in the reconstruct current block Bc in the memory 1306 with generation.Computing module 1304 can be realized the step 24 of coding/decoding method.Decoding device 13 also comprises prediction module 1308.Prediction module 1308 is confirmed predict blocks Pr.Prediction module 1308 can realize the step 22 according to coding/decoding method of the present invention.The step 20 of this coding/decoding method realizes in module 1300 and 1302.

Obviously, the present invention is not limited to the above embodiments.Especially, those of ordinary skill in the art can be with any alternative applications in said embodiment, and makes up them so that from their various advantages, benefit.Therefore, the present invention is not limited to employed alternative types (for example, DCT, wavelet transformation, DFT etc.).Equally, can change the scanning sequence (for example, raster scan (raster scan), zigzag (zigzag) etc.) of pixel.In addition, the present invention will never receive mode (for example, SSE, SAD, the Max etc.) restriction of calculating energy level.

The present invention is applied to the coding of still image or image sequence.

Claims (14)

1. one kind is called the method for the block of pixels of current block through spatial predictive encoding, and it comprises following steps:

-through utilizing current threshold value the coefficient from the conversion on the window that is applied in the said pixel that covers said current block is at least added threshold and through being applied to the said inverse transformation that adds the threshold coefficient, is definite (10) predict pixel of each pixel of said current block;

-from said current block, extract predict blocks that (12) is formed by predict pixel with the generation residual block;

And

-coding (14) said residual block,

Said method is characterised in that from the contiguous reconstructed pixel of current block to be confirmed or the said current threshold value of encoding.

2. according to the described method of claim 1; Wherein utilize each threshold values of a plurality of threshold values to repeat to confirm for each pixel of said current block the step of predict pixel, this method further comprises and is chosen in the minimum threshold value of the predicated error calculated between current block and the predict blocks in the middle of a plurality of threshold values as current threshold value.

3. according to the described method of claim 2, wherein through with the said current threshold value of differential coding of prediction threshold value, this predicted value depends on the contiguous reconstructed pixel of current block.

4. according to the described method of claim 3, wherein said prediction threshold value equals to be used in the mean value of the threshold value in the contiguous block of said current block.

5. according to the described method of claim 3, wherein said prediction threshold value equals to be used in the intermediate value of the threshold value in the contiguous block of said current block.

6. according to the described method of claim 3, wherein said prediction threshold value is confirmed according to following steps:

-through utilizing threshold value that the coefficient that is applied in the conversion gained on the window that covers said reconstructed pixel is at least added threshold and through being applied to the said inverse transformation that adds the threshold coefficient, for each reconstructed pixel in the adjacent domain of current block is confirmed predict pixel;

-utilize each threshold values of a plurality of threshold values to repeat to confirm the said step of predict pixel for each pixel of said adjacent domain; And

-be chosen in the minimum threshold value of the predicated error calculated between reconstructed pixel and the respective predicted pixel of adjacent domain of current block in the middle of a plurality of threshold values as the prediction threshold value.

7. according to the described method of claim 1, wherein said current prediction threshold value is confirmed according to following steps:

-through utilizing threshold value that the coefficient that is applied in the conversion gained on the window that covers said reconstructed pixel is at least added threshold and through being applied to add the inverse transformation of threshold coefficient, for each reconstructed pixel in the adjacent domain of current block is confirmed predict pixel;

-utilize each threshold values of a plurality of threshold values to repeat to confirm the said step of predict pixel for each pixel of said adjacent domain; And

-be chosen in the minimum threshold value of the predicated error calculated between reconstructed pixel and the respective predicted pixel of adjacent domain of current block in the middle of a plurality of threshold values as current threshold value.

8. according to claim 6 or 7 described methods; Wherein for each reconstructed pixel of the adjacent domain of current block, the predicated error of between the reconstructed pixel of the adjacent domain of current block and respective predicted pixel, calculating is considered their distances with respect to the edge of current block.

9. according to the described method of one of claim 2 to 8, wherein select said current threshold value for the current block of size 8 * 8, multiply by through the said current threshold value that will select strict with 1 alpha, for each piece of the size 4 * 4 of current block calculates current threshold value.

10. according to the described method of one of claim 1 to 5, the size of wherein said window depends on pixel to be predicted position in current block.

11. the method through the current block of spatial prediction decoded pixel, it comprises following steps:

-decoding (20) residual block;

-through utilizing current threshold value the coefficient from the conversion on the window that is applied in the said pixel that covers said current block is at least added threshold and through being applied to the said inverse transformation that adds the threshold coefficient, is definite (22) predict pixel of each pixel of said current block; And

-the said current block of predict blocks reconstruct (24) through merging said decoded residual piece and forming by said predict pixel,

Said method is characterised in that confirms said current threshold value from the contiguous reconstructed pixel of current block.

12. according to the described method of claim 11, wherein said current prediction threshold value is confirmed according to following steps:

-through utilizing threshold value that the coefficient that is applied in the conversion gained on the window that covers said reconstructed pixel is at least added threshold and through being applied to the said inverse transformation that adds the threshold coefficient, for each reconstructed pixel in the adjacent domain of current block is confirmed predict pixel;

-utilize each threshold values of a plurality of threshold values to repeat to confirm the said step of predict pixel for each pixel of said adjacent domain; And

-be chosen in the minimum threshold value of the predicated error calculated between reconstructed pixel and the respective predicted pixel of adjacent domain of current block in the middle of a plurality of threshold values as current threshold value.

13., also comprise following steps in addition according to the described method of claim 11:

The difference of-decoding threshold value;

-definite prediction threshold value from the contiguous reconstructed pixel of current block; And

-calculate said difference and said prediction threshold value sum, said and value is said current threshold value.

14. according to the described method of claim 13, wherein said prediction threshold value is confirmed according to following steps:

-through utilizing threshold value that the coefficient that is applied in the conversion gained on the window that covers said reconstructed pixel is at least added threshold and through being applied to the said inverse transformation that adds the threshold coefficient, for each reconstructed pixel in the adjacent domain of current block is confirmed predict pixel;

-utilize each threshold values of a plurality of threshold values to repeat to confirm the said step of predict pixel for each pixel of said adjacent domain; And

-be chosen in the minimum threshold value of the predicated error calculated between reconstructed pixel and the respective predicted pixel of adjacent domain of current block in the middle of a plurality of threshold values as the prediction threshold value.

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